P1406 EGR Pintle Position

Chris97K1500 · September 23, 2004

Well my 97 truck threw an SES light and used the scanner on it. Trouble Code 1406, EGR valve pintle position Circuit fault. Is this just time for a new EGR valve? Is it located next to the TB unit? Similar to pre-Vortec 350's? Thanks, Chris

budhayes3 · September 24, 2004

Hmm, could be the valve, but since the code says "circuit fault", it could be the wiring also. On my 99 the valve is actually an electronic solenoid located by the passenger's side exhaust manifold, not sure where it is on a 97 with the classic style small block. I'd first do a visual inspection and see if you find something that looks like it could be it. Check for unplugged connectors, melted, moldy or frayed wires. If you can access the egr valve, maybe try to unbolt it and see if you can get it to move. I'd definitely get my hands on a Helms or Haynes manual just to get you pointed in the right direction.

Oh yea, and if I haven't said it before, you have a real nice lookin truck!

Chris97K1500 · September 24, 2004

Thanks, for the compliment. I guess I'll have to look it over tomorrow for any wires that look bad. After looking it up on the internet, this code is a common problem with GM's older design for the EGR valve. The diagnostic sites said this problem is either due to carbon buildup in the valve, or it's just a bad valve in general. The circuit problem is sensed when it takes over 350ms for the valve to open, supposed to open in 50ms. Whatever all this number stuff means, I don't know, but a new EGR is the route to go. Hopefully it's something as easy as this. I'm going to let the Scanner run in monitor mode while I'm driving to get real time data. Hopefully that's all it is. Thanks, again. Chris

budhayes3 · September 24, 2004

So it sounds like the EGR valve is sticking and taking too long to move...350 milliseconds as opposed to 50 milliseconds. Probably all gummed up with carbon. If the wiring all looks good, then the EGR valve is more than likely your problem. Can't see it being too expensive...might even be able to try and clean the old one with some carb cleaner and WD-40...worth a shot if you're gonna plan on gettin a new one anyway. Let us know how you made out.

rjgogo · September 24, 2004

had the same code being thrown on my old 97 Tahoe, a month or two before I was going to trade it in I figured I better fix the check engine light. Took the EGR valve out, Cleaned it and put it back in. No more Check engine light, well at least for a month or two, but it would usually throw that code all the time. Cost nothing

Bluesman123 · September 25, 2004

Bud and RJ are probably right. Try cleaning it with carb cleaner. If that doesn't work ask you dealer if they have any updates on the code they flash into your VCM. I had the same problem, same codes, even replaced the valve, same codes, had the dealer reflash the VCM (part of another project) and the codes went away. I think there may be a tech note on this problem.

Dave

Chris97K1500 · September 25, 2004

Well I cleaned it first after I saw the $110 AC Delco replacement, code came back after I used the scanner to clear all codes. So I went and bought it, put it in, no codes, truck seems to be smoother all around. So far, no more codes. Thanks, Chris